I have a queen sheeeeeekeeeee boooootonnnn. I live alone and in a humid climate. I had to get a bedframe. If I had to move or get another futon in the future I would probably go with a full. I had to roll up my queen and tie it with a rope to move it. It’s heavy as fuck. I was just moving rooms not cleaning it. I’m a very strong woman. However it was easier to move than say a queen sized mattress. Also rolling it is more compact. If you plan to do the traditional cleaning on them and really shake it outside ? Go with the double twins. If you have any doubts that you might not like the floor or there is the possibility of mold those double twins won’t fit on a normal frame. Go with the full sized. Seems like most of us fantasize about Japanese Minimalism until we can’t sleep from numb arms or pressure point pain. I can’t sleep on my futon without a memory foam topper. I have 2 toppers. But cost of toppers plus futon are way less than a gallery quality mattress and I like that I can control the firmness or fluff depending on how many layers I want. Answer from makingbutter2 on reddit.com